diff --git a/poi/src/test/java9/module-info.java b/poi/src/test/java9/module-info.java
index 58ac2220c5..7a6de063c1 100644
--- a/poi/src/test/java9/module-info.java
+++ b/poi/src/test/java9/module-info.java
@@ -106,6 +106,7 @@ module org.apache.poi.poi {
     requires net.bytebuddy;
     requires org.junit.jupiter.api;
     requires org.junit.jupiter.params;
+    requires org.apiguardian.api;
 
     exports org.apache.poi.hpsf.basic to org.junit.platform.commons;
     exports org.apache.poi.hssf.record.pivot to org.junit.platform.commons;